We report a long-surviving case of retroperitoneal liposarcoma requiring 6 operations in 24 years. A 56-year-old female was diagnosed with liposarcoma and it was resected for the first time in 1991. The pathological diagnosis was well-differentiated liposarcoma. Thereafter, we resected recurrences in the retroperitoneum in July 2008, with the left half of the colon in June 2011. Then, we resected the pancreatic tails, spleen, accessory spleen, left adrenal gland, left kidney, and part of the diaphragm in October 2012, and part of the diaphragm, descending colon, and jejunum in October 2014. At this time, there were growing recurrences removed from the pancreatic tails. There is no evidence of recurrence after 24 years after the first resection. In this case, it was thought that the factor correlated with long survival was actively resecting recurrences and recognizing high-grade dedifferentiated type liposarcoma at an early stage.